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Originally posted by GTS-t VSPEC

How many of the race cars run with PowerFC's around Waneroo racecourse? None. How many use Wolfs? About half.

I'll keep that in mind if I ever decide to go racing at Waneroo. :D

Seriously, what are you trying to accomplish with the above statement?

Edit: I respect your car (411rwhp is impressive) and I respect your choice of ECU, but why do you have to slag off other people's choices, without even providing any substantial evidence of why your choice was better? The Wolf is probably better for you, and it probably is better for people at Waneroo. But why does that make the PowerFC crap?

I think that the fact that there are so many really defensive Wolf people in here can only mean they're a little insecure about its shortcomings.

When did I say the PowerFC is crap? I'm not knocking the PowerFC, is does an adequate job, but doesn't provide the level of additional features that you may need if you want to go racing, that was the point I was making, so chill-out.

JimX, When was I slagging off other people's choice in ECU. Sydneykid (who I have alot of respect for) wanted to know why we thought that the Wolf was better than the PowerFC, I was just highlighting that it has many auxillary inputs and outputs, which are useful in many applications. NOS control, staged injectors, etc.

I'll take my own chill-pills too:D

Hi GTS-t VSPEC, when we build a race only car (not a road car or an all round car) we only use Motec. To pinch your phrase, how many cars with ECU's (all of them, not just the dinosaurs) racing at Bathurst last weekend were using Motec? Ohh about 80%.

I don't think we really want to do the Motec versus Wolf do we?

I've run PFC on both my old S15 and now on my GTR.

The big issue that I had on the S15 PFC was that there was no (accessible) inlet manifold air temp compensation. This meant that what was considered a conservative tune in the cooler months, became dangerous during Perth's hot summer and I believe was a fundamental cause in destroying no. 2 piston. After the engine rebuild, we did dyno testing with the old tune parameters and actually heard detonation (using microphone pickup), however the Nissan knock sensor never went beyond 30 as shown on the PFC. There was not at the time (nor is there now I believe) a Datalogit available for the S15 to adjust air temp. compensation.

I knew all of these short comings when I decided to go PFC for my GTR, however the basis of my decision was that there are plenty of second hand (read cheap) PFCs available for the GTR (R32/33) and I have access to a Datalogit for this model.

As it turns out, the GTR PFC has air temp correction available through the handset and with the twin knock sensors seems to give much more reliable information and therefore, IMHO, a safer tune.

I have seen a fair bit of tuning done at SST with both the Wolf and the PFC and I think that it is a credit to Steve that he has taken the time to learn the PFC and is purchasing the Datalogit in order to be able to tune it better. This is despite him being a Wolf dealer. There is only one (or two at the most) other tuner that I know of in Perth that doesn't bag the PFC.

In conclusion which would I choose again? Definitely Wolf P&P for the SR20 motor, definitely PFC for R34 GTR (in order to keep the center display and avoid piggy back setups) and the R32/33 GTR - well let's just say I'll be looking VERY closely at the new Wolf P&P when it's fully released.

Hope the above comments add to the discussion.

Hi Gav, the reason the PFC in Silvias don't have inlet air temperature compensation is because Nissan doesn't equip them with an inlet air temperature sensor. Whereas the GTR does have an inlet air temperature sensor (it is located at the front of the plenum).

Ditto one versus two knock sensors. These are a couple of the reasons why Nissan charges more for a GTR than a Silvia.

So if you use a Wolf P&P on a Silvia and you want inlet air temperature correction then you have to buy an inlet air temperature sensor. Then fit it to the standard plenum and run the necessary wiring harness. This is hardly P&P.

If you want 2 knock sensors (or a more sensitive one) to use with the Wolf you have to buy it/them and fit it to the Silvia. Once again this is hardly P&P.

In summary, you are comparing a P&P Power FC with a Wolf that is most definitely not P&P.

Hope that adds to the thread.

Sydneykid

Valid point that the PFC can only use the OEM sensors that Nissan fit. In fact, I find the diagnostics screen bloody useful - it helped me identify a dirty AFM as well as recalibrate the TPS for a more stable idle.

Granted also that adding an air temp. sender (either by need or desire) cannot be considered P&P, but it's also not rocket science! Likewise for adding a MAP sender if you want to do away with the AFM(s). I wouldn't imagine that setting these up on any aftermarket ECU (Wolf, Autronic or Motec) would be difficult or time consuming to a tuner who is familiar with the ECU.

My point is that it is nice to have the option of additional inputs should you want to. If/when I find myself with another SR20 equipped car, it will definately not be the PFC based on my previous experiences.

For the moment, however, the PFC does everything I need it to for the GTR and probably will for the future.

Sydneykid, does the RB25 have air temperature sensors for PowerFC temp compensation? If so, are the settings too conservative for our hot summers? And does the RB25 have 1 or 2 knock sensors? (and likewise does the PFC read from both if it has 2)

Sydneykid please don't think i'm busting your balls but you make factual comments that arn't facts because if you were right up with supercars you would know that Motec are the control ECU this year so its 100% Motec and we are not talking that end of the market we are talking cheap plugins.125rpm load sites is more than 16. Theirs no air temp sensor on an RB25 this is why Wolf allowed this to be added and its worth running 2 wires on a hard core car i'd say.PowerFCs failing is not making the software avalible for finer quicker tuning, their can be no denying that.

Does not having 6 sequential injector drivers (4 from wolf) really use that much fuel due to 2 sets of injectors firing twice?

I'm not really familiar with how it works.

And if tuned at say 12:1 AF could it cause a lean condition on 2 of the cyclinders that have the injectors firing once compared to the others firing twice?

Originally posted by Steve-SST

PowerFCs failing is not making the software avalible for finer quicker tuning, their can be no denying that.

It's not so much a failing as a marketing ploy designed to make Apexi more money so they'd probably view it as a success :D Hopefully the Datalogit thing will help alleviate this situation. No it's not perfect, but a step in the right direction for the end-user's wallet I think.

Joel, the Wolf wouldn't fire 2 injectors twice, what it would probably do on a 6 cyl engine is fire 2 injectors sequentially, then batch fire 2 lots of 2 at the same time.

So it might squirt something like this: injector 1 when cylinder 1 needs fuel, injectors 2 and 3 when cylinder 2 requires fuel, injectors 4 and 5 when cylinder 4 requires fuel, then injector 6 when cylinder 6 needs fuel. (my numbers used in this example are almost certainly wrong due to firing order).

That's still a step up from how my VS Commodore fired the injectors, which was all at once!!! Almost defeats the purpose of having fuel injection, because that's essentially how a carburettor works.

So many questions, let's start with Steve-SST, yes Steve I know that Motec is the control ECU for the Supercars but I included ALL the ECU equiped cars racing at Bathurst on the weekend. That's why I said "how many cars with ECU's (all of them, not just the dinosaurs)".

Hi JimX RB25DET's have multiple knock sensors, pretty sensitive ones at that. I think Steve answered your other questions perfectly.

Hi Joel, certainly firing 2 injectors at once is not as fuel efficient as full sequential. As for how much, I have not tested it on a Skyline so I can't really say. It is noticeable (5% is not unusual) on other cars, so I see no reason why Skylines would be different.

As for lean cylinders, all the cylinder's injectors fire twice per cycle. So one cylinder is not leaner than another. Simply put, the fuel just hangs around in the inlet tract until the next cycle (the inlet valves open). This gives the fuel time to de-atomise so it doesn't mix with the incoming air so well. Since it is not dispersed as well it doesn't burn as efficiently and thus doesn't produce as much power. So you use more fuel to produce the same amount of power. Strangely, the lower the RPM the worse the fuel economy suffers, this is due to the longer time for the fuel to de-atomise. So cruise fuel economy suffers more than high rpm WOT running.

On your example, with 4 injector drivers, you would only use 3, and connect 2 injectors to each driver. The unused (4th) driver would be dissabled in the software. Basically the same with ignition drivers. use 3 dissable 1.

I hope that answered all the questions.

I thought the Ecotec has sequential injection, where the Holden V8 (as used in VN-VS) does not. Well, I was told by my mechanic at the time that those V8s use batch fire, I can't remember where I read about the Ecotec being sequential. I could be wrong about both.

Sorry GAV, I missed something in your earlier post. On the Power FC's we always set the detonation warning at 20. As you have found, 30 can be a problem.

My phylosophy for selecting Skyline ECU's is pretty simple. On road cars or combination road and track cars, I use Power FC's. Not perfect but good alround. For full time race cars I use Motec ECu's, because we have a lot of in house expertise and they are arguably as good as anything else in the world. I reckon if you can't afford a Motec, then you can't afford to race. All the other stuff on a race car cost SO much, that the grand and half more for a Motec is almost insignificant. For example, a set of tyres costs more than the difference, and we use a set and half every meeting on the GTR's. Skip one meeting and you have paid for the Motec.

That's my thoughts on ECU selection.

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